<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
</head>
<body>

<div id="app">
    <!-- <input type="text" v-model="message"> -->
    <!-- <input type="text" :value="message" @input="valueChange"> -->
    <input type="text" :value="message" @input="message = $event.target.value">

    <h2>{{message}}</h2>   
</div>

<script src="../js/vue.js"></script>
<script>
    const app = new Vue({
        el: '#app',
        data: {
            message: '你好啊'
        },
        methods: {
            valueChange(event) {
                this.message = event.target.value
            }
        }
    })
</script>

</body>
</html>